Apparatus for evaporating alkaline solutions



' (No Model.)

- v 2 SheetsSheet 1 J. P. R. POLK. APPARATUS FOR EVAPORATING ALKALINE SOLUTIONS.

No. 305,681. I Patented Sept. 23, 1884.

(No Model.) 2 Sheets-Sheet 2.

v J; P. R. POLK.

APPARATUS FORE-VAPORATING ALKALINE SOLUTIONS. I No. 305,631. Patented Sept 23, 1884.

Wzfnemes nyenibr Units STATES.

JOHN P. R. POLK, OF WILMINGTON, DELAVARE, ASSIGNOR TO THE UNIVERSAL OONGENTRATING COMPANY, OF CAMDEN, N. J.

APPARATUS FOR EVAPORATING ALKALINE SOLUTIONS.

SPECIFICATION forming part of Letters Patent No. 305,631, dated September 23, 1884.

' Application filed April 28. 1883. (No model.)

To aZZ whom it may concern:

Be it known that I, JOHN l. R. POLK, a citizen of the United States, residing at VVilniington, in the county of New Castle and State of Delaware, have invented certain new and useful Improvements in Vacuum-Pans and Apparatus for Evaporating Alkaline and other Solutions, and the Desiccation of any Materials Containing Moisture, of which the,

following is a specification. V

' My invention relates to improvements in apparatus intended more especially for the evaporation and concentration of alkaline solutions, though it is applicable to any furnace or apparatus employed for the eXpulsion or evaporation of water or other liquid from any material.

bustion from the igniting and calcining furnaces.

My invention also relates to means, hereinafter more fully described, for preventing the liquid from being forced over by ebullition into the condenser.

. In order that my invention may be more fully understood, I will first describe it with reference to the accompanying drawings, and then point it out more particularly in the claims.

In the drawings, Figure 1 represents a side elevation of my improved apparatus, part being in vertical section. Fig. 2 is a plan view thereof, partly insection; and Fig. 3 is a sectional view of the boil-over reservoir detached.

A may represent any suitable furnace, here shown as being employed both for the purpose of heating the liquid in evaporatingpan B and at a latter periodof the process of recovery of soda-ash or other alkali, igniting and aiding the combustion of material in the calcining-furnace C. On each side of the furemploy a simple arched support, or, if a horizontal stationary furnace be used, may support the flue directly on top of the furnace. From the flue F the gases are led to the stack.

The vacuum-pan B may be either vertical, as shown, or horizontal, and is preferably provided within with agitators Z, of any approved construction-perpendicular or horizontal. It may either connect immediately with the furnace through pipe I, or may connect with an intermediate reservoir, J, from which the material may be discharged into the furnace.

The pan is charged through pipe mfrom reservoir M, in ordinary manner. any suitable part of the pan, I place the vapor-discharge pipe N, and within this pipe, to prevent the carrying over by ebullition of bubbles of the liquid into the condenser, I place a diaphragm, O, or system of diaphragms of wire-gauze, which break the bubbles, while allowing free passage of the vapor and facilitate the return of the liquid to the evaporating-pan. To facilitate the return of the liquid on the bursting of the bubbles against the upper diaphragm, O, I place within the pipe N a second pipe, P, having upon its upper end a second diaphragm, Q, of wire-gauze to still further arrest the bubbles. The liquor from bubbles bursting against the upper diaphragm (or diaphrams, if a number be employed,) is returned around the pipe I? to the vacuum safe or trap T, whence it flows back into the pan. The pipe N is led into a boil-over chamber, It, whence the liquid is returned to the pan through pipe S. A circular flange, T, around the bottom of pipe N, into which pipe I? dips, arrests sufficient of the return liquid to make a vacuumsafe at this point, and pre On top, at

pan with a forced exhaust, with or without agitators and with or Without condensers, and

' pan.

an interposed bubblebreaker produces a strong and effective evaporatoiyworking with great speed without the passage of any liquid over into the condenser. An agitator should generally be employed, as it greatly increases the rapidity of evaporation, and is an important improvement over the ordinary vacuum- By my method the heat from the calcining-furnace and lighting-furnace heats the bottom of the evaporating-pan, while the return-flue heats the sides thereof to the height of the liquor therein contained, thus more fully utilizing the waste heat, and saving all coal expenditure for boiling the soda in the process of evaporation, a larger portion of the Waste heat from the incinerating-furnace resulting from the combustion of organic inatter in the soda. The vacuum-pump also takes the place of a large quantity of coal by'utilizing to the highest degree the heat generated. Having thus described my invention, the following is what I claim as new therein and desire to secure by Letters Patent- 1. The combination, with a suitable evaporating and calcining furnace, of the returnflue having branches surrounding the sides of the evaporating-pan, substantially as set forth. 7 2. The combination, with a suitable evaporating and calcining furnace, of a return-flue having branches surroundingthe evaporating pan, .said branches being divided centrally 'and provided with a suitable damper, as set forth.

3. I11 combination with a direct vapor-dis charge pipe, the ebullition-guard consisting of one or more diaphragms of wire-gauze placed transversely in said pipe, substantially as described.

4. The combination, with an evaporating vessel or vacuum-pan, of the vapor-discharge pipe, having one or more perforated diaphragms arranged therein, and an interior pipe concentric therewith and having a similar diaphragm, and the flange forming a vacuum-safe, in themanner set forth.

5. In combination with the vapor-discharge pipe and a -boil-over reservoir, the pendent flange therein, serving to arrest and precipitate liquid passing through the reservoir, whence it is returned to the evaporating-pan by asuitable pipe emptying intoa vacuumsafe, substantially as set forth.

6. The combination of an evaporating-pan,

an ebullition-guard in the exhaust-pipe thereof, and vacuum-pump, or other force-exhaust mechanism, substantially as set forth.

7. The combination ofan evaporating-pan having suitable means of agitation, an ebullition-guar'd in the vapor-exhaust pipe thereof,

and a vacuum-pump, or other force-exhaust 

